Semiconductor device

A semiconductor device is an electronic device whose conductivity is between a good conductor and an insulator. It utilizes the special electrical characteristics of semiconductor materials to complete specific functions. Semiconductor devices use different semiconductor materials, different processes and geometric structures to develop a wide variety, Electronic components with various functional uses.

Common electronic components like zener diodes, varistors, etc. are semiconductor devices. Zener diode and varistor, which are both semiconductor devices, which one is more powerful? Since Zener diodes and varistors have different working principles, their functions and applications are also different.

Zener diode

Zener diodes, also known as Zener diodes, are made of semiconductor silicon materials and belong to semiconductor devices. They use PN junctions to reverse breakdown, and their current can vary in a wide range while the voltage remains basically unchanged, which has a voltage stabilizing effect.

working principle

Diodes are usually forward-conducting, reverse-blocking, and unidirectional. However, if the reverse voltage applied to the diode exceeds the capacity of the diode, the diode will break down and be damaged.

However, there is a kind of diode whose forward characteristics are the same as those of ordinary diodes, and its reverse characteristics are quite special: when the reverse voltage is applied to a certain level, the diode presents a breakdown state, and a larger current passes through without damage, and the diode presents a In the breakdown state, although the voltage flowing through the diode changes greatly, the voltage across the diode changes very little, which acts as a voltage regulator. Such a special diode is called a Zener diode. According to its voltage stabilizing characteristics, it is used for voltage stabilizing power supply, and it is mainly used as a voltage stabilizer or voltage reference element in the circuit.

Varistor

The varistor is a new type of voltage-limiting protection element. It is made of semiconductor materials and has nonlinear volt-ampere characteristics. Its resistance is sensitive to voltage. Within a certain current and voltage range, the resistance of the varistor increases with the voltage change with change.

working principle

When the threshold of the varistor itself is greater than the voltage applied externally to the varistor, the current passing through the varistor is extremely small, and the varistor is in an off state at this time.

When the external voltage applied to the varistor is greater than the threshold value of the varistor, the current through the varistor increases and the resistance value decreases. At this time, the varistor is in a closed state, which reduces the influence of the voltage on the circuit, thereby protecting Other electronic components are often used for power overvoltage protection and lightning protection.

Zener diodes and varistors play an important role in their respective applications due to their own characteristics. The same is true for other electronic components, which can only play their own role when they are used in suitable occasions.